Chain link



H. ST. PIERRE GHAIN LINK Filed Feb. 3, 1943 Patented May 21, 1946UNITED` sTATEs PATENT OFFICE CHAIN LINK Henry St. Pierre, Worcester,Mass. Application February 8, 1943, serial No. 474,569

1 olaim. (01.59-84) This invention relates to new and improved chainlooking links. i i

Objects of the invention include the provision of looking links of bothstud and plain type and comprises two similar, forged link end pieceswhich are formed in the shape of a`C or U, each piece having a pair ofvgenerally similar ends which are provided With shouldered lookingheads, there being a connecting piece or pieces for securing the two endpieces together, said connecting piece or pieces being providedoriginally With means forming apertures or holes` for receiving theshouldered heads on the end pieces, and said connecting piece or piecesbeing Originally forged with more metal than is necessary merely toconnect the end pieces forthe purpose of providing a strengtheningbulged section in the connecting piece or pieces at the point requiringadditional strengthin the connecting piece.

Difiiculty has always been present in making strong forged looking linksfor chains because the female members in the lockinglinks have beenfound to have Vcross sections which are too thin and weak, or in caseswhere the female member is made sufiiciently large, the male member hasbeen found to be too weak for chains which are used in applicationsrequiring great strength. The present invention iprovides a looking linkand method; of making the same in a simple but extremely effectivemanner to provide a chain link of the looking type whichV will not breakat the looking connection.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to drawing in which V Fig. 1 is a plan view of alink made according to the invention and showing the connection part insection;

Fe'. 2 is an edge view of the link of Fig. 1 and looking in thedirection of arrow 2 in Fig. 1, the connecting piece being in section;

Fig. 3 is a view showing the manner of assembly of the looking link;

Fig. 4 is an edge view of the connecting piece looking in the directionof arrow 4 in Fig. 3;

Fig. 5 is a view partly in section 'showing a modified form ofconnecting piece and Fig. 6 is a section through another form ofconnecting piece.

The present invention may be applied to plain or stud links but it hasbeen eleoted to disclose the invention as applied to a stud link. It isto the accompanying be understood that the invention is applied tolooking links which are used to connect solid links for the assembly ofchain and for that reason the looking link must embody means providingfor the assembly of a solid link at each end of the looking link priorto the finishing connection of the looking link parts.

In Fig. 1 there is shown a pair of end pieces for the link, these endpieces being indicated generally at |0. End pieces |0 are exactly alikeand may be forged in the same or similar dies. Each end piece I 0 isforged in ,a die in a C or U shape, and having free ends as at |2. Eachof the end pieces has two ends 12 and each end |2 is provided with ahead M forged simultaneously and in the same die ,with the body of theend piece. It will be seen that each head M is relatively large andheavy and is connected to the body of the pieces I 0 by means of areduced looking neck 16, the necks |6 being of relatively large crosssection as compared to the usual male connection member of a lookinglink, but the shoulders |8 which are formed between the heads o i4 andnecks IB are sufiicient to provide an abutment for looking the endstogether by means of the connecting piece 20 to be described.

The connecting piece 20 is a unitary forged piece in the case of a studlink, and in the form shown comprises a dumbbell-like element having awaist 22 and a pair of enlarged ends`2`4, said ends being alike andOriginally forged along lines 25 to form a neck d tapered aperture asindicated in Fig. 3.

When the connecting piece 20 has been originally forged as abovedescribed, it may be punched out along line 26 in Fig. 3 to removematerial from the interior of the end pieces 24 and also to remove anyfin which may have been left in the forging action so that when theconnecting piece 20 is ready for assembly, it is provided with aninterior passage along lines 26 of a size to receive the heads |4 asindicated in Fig. 3. Obviously, the two `l1`nks 28 are applied to endpieces |0 just prior to the assembly of the end pieces with theconnecting piece 20.

End pieces |0 having been set into the passages 26 in the connectingpiece, the latter is heated and is then forged in a die to force themetal of the connecting piece ends 24 to flow closely lbehind Shouldersl8 of heads |4 to completely fill and surround necks 16 in the mannershown in Fig. 1. The ends of lthe connecting pieces 20 are Originallyprovided with what may be termed a surplu'sof material so that the finalsection of the end piece 24 at neck |6 and heads |4 is relatively largeand is clearly sufiicient to f 2 vent breakage and to hold the ends Illtogether until the end pieces H] themselves are broken under severetesting. Referring to 'igs. 1 and 2 it will be seen that the so calledsurplus metal of the ends Eli provides a bulge along a line 39 allaround heads Hi and neck IG, and by reason of the bulge the metalsection at the necks is similar to the section at the heads. In otherWords the bulge along lines 3il is of a form to provide a heavy sectionwhere it is needed in the connection member at the heads Ill' as Wel1 asat neck Hi, and the increase in metal section due to the enlargement ofheads IB relative to necks Hi, is compensated for by-the fact that thebulge 3G is bulged out'wardly at its greatestV extent in the region ofthe heads and less so at the rei duced necks.

The bulge which is occasioned by the present construction isunobjectionable in most cases and does not interfere with the operationof the chain and does not impair the usefulness or appearanc'e thereof;and at the same time the bulge provides for strengthening of the femaleconnecting member' at the exact point where such strengthening is themost desirable. In other words the section of the female member issubstantially uniform regardless of the presence of the reduced lookingnecks Hi.

In the form shown in Figs. 1 and 2, the bulge line 3% terminatesapproximately at the point of wider section of end pieces IO, but it isalso provided as shown in Fig. 5 with a means of streamlining the bulgeby forging some of the extra material of the connecting pieces alongover the ends 12 of the end pieces IE! as is clearly shown at 32 in Fg.5.

As is Well known in. the art, the points of connection of looking linkscarry only one-half the load of the link because this load is splitbetween the two 'connections The Optimum conditions of looking links isto provide a construction wherein lthe link 'will break under test at apoint inthe end pieces .lfl rather than in the connection betweenthe endpieces. This condition is extremely hard to obtain due to the fact thatthe ordinary looking link must sacrifice metal section either Vin themale or femaleconnecting piece, and this weakens the connection eventhough only one-half 'the load is on each connection, and a good exampleof Athis difficulty is illustrated in the prior art in the patent toLutts et al., 1,974,827, wherein the female member as at M in Fig. 10has been sacrificed to provide a relatively strong male connecting piecesection as at 26 in Fig. 3 of this patent. rThe present inventionprovides for equal strength in bothconnecting members and it alsoprovides-a construction wherein the strength of the connection is seento be uniform in spite of Variation in the section of metal betweenheads Ill and necks 16.

In order to obtain the Optimum conditions above described, the presentinvention provides for an irregular non-circular or ovoid form in thefemale parts 24 of the stud or connecting members. This conformation isseen by Comparing Figs. 1 and 2, wherein the Curved or bulged section isgreater at the lateral aspects of the link as at 34 than at the edgeaspect as at 36. Thus both sides of the parts 24 are heavy and thick andthe single edge at 36, although strong, is thinner and extends along aflatter curve. It is contemplated that edge 36 may even be substantiallystraight, or curved slightly to merge with ends E2 uniformly in caseswhen the entire link is oval.

By this construction the link presents no obstructions to sheaves or thelike in cases where the chain passes through openings, since thestrengthening bulges as at 35 lie almost entirely at the sides of thechain looking links, rather than at the edges, the latter extending thefurthest outward of any part of the chain from the axis thereof.

Fig. 6 shows a modificat'ion wherein connecting heads 38- are merelyenlargements of the chain link ends |2a, and in this case thebulge 40extends substantially outwardly laterally but not so much at the chainedge, it being noted that Fig. 6 is a view taken in the same relation tothe link -as Fig. 2.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forth in the claim, but what I claim is:

A looking link comprising three parts, two of said partsbeing similarC-shaped end pieces and each piece having a pair of ends, a reduced neckat each end andl a head forming a shoulder therewith on each neck; andthe third part comprising a stud, means forming passages in the stud,correspondin-g headsand necks of the C-shaped end pieces being locatedinpairs in separate apertures, said stud in the region of the passagesbulging outwardly on curved 'lines at the edges but principally at thellatera'l aspects of the link to provide increased metal Sections in thestud adjacent the heads and necks, the bulges of the stud being alongCurved lines which extend outw-ardly o-f the link to a greater extent atthe heads than at the necks to provide an approximately uniform area ofsection at the heads and necks. v

HENRY ST; PIERRE.

